Temporal Reuse in Cooperative Relay Networks via Destination Feedback

Cooperative relaying is a low-complexity diversity technique to combat transmission impairments due to multipath fading and path loss. A common approach to maintain orthogonal transmissions required to achieve diversity is through time-division multiple access (TDMA), which schedules a source node to transmit and then defers a new transmission until the relay retransmission finishes. To avoid such a delayed transmission, cooperative relaying with temporal reuse has been suggested, which allows the source nodes to transmit continuously by sharing the same temporal resource with the relay nodes. However, simultaneous transmissions introduce cochannel interference (CCI), resulting in complete diversity loss. Motivated by incremental relaying (IR) that utilizes destination feedback to improve spectral efficiency for interference-free cooperative networks, this paper studies how cooperative relaying with temporal reuse can benefit from destination feedback. In this context, since cooperative relaying is enabled only when the source transmission fails, transmission outcomes between two consecutive slots become correlated. A Markov-chain-based model is developed to capture such dependence and allows for the derivation of critical performance metrics, including the outage probability and the stability region, all in closed form. Through numerical results, we validate the analysis accuracy and discuss the improvement and limitations of cooperative relaying with temporal reuse via destination feedback.